In the field of aviation, communications networks serve to convey communications that are internal to an airplane, which communications serve mainly to exchange data between various elements of the avionics or even within a single element of the avionics.
Usually, a communications network has modules (computers, processors, . . . ) that are put into communication with user terminals via switches in order to exchange data within a given module or between a module and a user terminal, the switches being configured to monitor and distribute the various data frames of the various logical channels of the network on the basis of configuration tables containing the characteristics specific to each logic channel and to each outlet port associated with the switch in question.
FIG. 1 is a diagram of a prior art communications network. In that communications network, a first switch 1 controls both exchanges of data between the various portions of a given first module 2 and also exchanges of data between said first module 2 and a second switch 3 (drawn with continuous lines). The second switch 3 serves to control exchanges of data (drawn with bold continuous lines) between the first switch 1 and user terminals (not shown). In the same manner, a third switch 4 controls both exchanges of data between the various portions of a given second module 5 and also exchanges of data between said second module 5 and the second switch 3 (drawn in continuous lines). The second switch 3 thus also controls exchanges of data (drawn with bold continuous lines) between the third switch 4 and user terminals.
Each module 2, 5 thus requires the presence of a dedicated switch 1, 4 to put it into communication with another switch 3 that may possibly be shared in common with other modules. The presence of two switches in cascade for each module is necessary, specifically to ensure independence for data exchanged firstly within a given module (a portion of data drawn using dashed lines in FIG. 1) and secondly outside the module with user terminals (a portion of data represented by chain-dotted lines).
Such a communications network thus presents an architecture that is relatively burdensome and that includes in particular a large number of switches.